It is proposed to study pulsatile flow and mass transfer in physical and mathematical models of curved and branched arteries. The study is primarily motivated by recent work in our laboratory which uncovered a new mechanism (called "resonance") for large shear stress elevation during pulsatile flow in curved arteries. Resonance may play a role in the diseases of the large human arteries, particularly atherosclerosis. The broad objectives of the proposed research are to: (i) determine the spatial and temporal distribution of (artery) wall shear stress and mass transfer rate during pulsatile flow through curved and branched arteries, particularly under resonant flow conditions; (ii) determine the extent to which resonance occurs in the cardiovascular system; and (iii) determine the mechanism of resonance. These objectives will be pursued through four activities: (i) flow/pressure drop measurements in physical models of curved and branched arteries; (ii) oxygen polarographic electrode measurements of local wall shear stress and mass transfer rate in physical models of curved and branched arteries; (iii) numerical (computer) simulation of periodic flow and mass transfer in curved arteries; and (iv) flow visualization studies in curved artery models. The results of the research will improve our understanding of complex cardiovascular flows and associated mass transfer phenomena while shedding light on mechanisms of large artery disease, particularly atherosclerosis.